Jason Day has battled injury and adversity to be among the best players of his generation.

After several close calls, Day won his first, and to date only, Major in 2015. Day was the first man in history to card 20-under at a Major, shooting 268 at Whistling Straits to win the PGA Championship.

Day's father Alvin got him into the game as a six-year-old, registering him as a junior at their local club in the small Queensland town of Beaudesert.

He proved both an accomplished junior and a promising amateur, turning professional at the age of 18. A year later, he became the youngest winner of a PGA Tour sponsored event when he claimed the Legend Financial Group Classic, a Nationwide Tour event held at Stonewater Golf Course in Highland Heights, Ohio.

Day's momentum was halted by a wrist injury that kept him out of action for most of the second half of 2007.

He came close to notching his first PGA Tour win at the 2009 Puerto Rico Open, where he missed a birdie putt at the 18th in his final round and lost out on a chance to force a playoff.

Day earned a breakthrough win at the 2010 HP Byron Nelson Championship in a tournament from which he very nearly withdrew due to illness. He had endured a sinus infection and wasn't feeling great ahead of his first round.

After winning his first Major, Day was awarded the inaugural Greg Norman Medal and would claim the honor again in 2016.

Day has represented Australia at the World Cup once, in 2013, and has made the International team for the Presidents Cup on four occasions.

He has a street named after him in his hometown of Beaudesert.

After his family moved to the larger city of Rockhampton, Day started making a name for himself at regional golf tournaments.

In 2004, he won the Callaway World Junior Championship for boys aged 15 to 17. He also successfully defended his Adina Watches Junior Tournament title and won the Queensland Amateur, Australian Boys' Amateur and New Zealand Under 19 Championship events.

Day claimed the Australian Junior Order of Merit twice and as a teenager was a member of Golf Australia's Senior National Squad.

As an 18-year-old, he won the Australian Amateur Stroke Play and the NEC Master of the Amateurs.

Day made two European Tour starts as an amateur but missed the cut in both tournaments.

Directly after winning the 2006 Master of the Amateurs at the Yarra Yarra Golf Club, Day turned professional and began entering PGA Tour events on sponsors exemptions.

From July 2006 until the end of the season, Day entered six Tour events, making the cut five times. His best finish was a tie for 11th at the Reno-Tahoe Open.

Day entered the PGA Tour Qualifying Tournament but failed to secure his Tour card after splitting 119th place.

He joined the Korn Ferry Tour in 2007 and recorded 10 top-25 finishes on his way to ending fifth on the money list. His biggest purse was the $94,500 he claimed for winning the Legend Financial Group Classic presented by Cynergies Solutions.

Despite an underwhelming 2008 season, Day retained conditional membership of the Tour after a season where he missed the cut 15 times in 28 starts.

He made progress in 2009 and secured his status on the PGA Tour with a second-placed finish at the Puerto Rico Open.

In 2010, Day showed he wasn't going away any time soon by becoming the youngest Australian to win on the PGA Tour. In a wild finish to the HP Byron Nelson Championship, both Day and playing partner Blake Adams hit their approach shots into the same water hazard on the 18th. Adams double-bogeyed, forcing Day to make a 14-foot bogey putt for the tournament. Day obliged, leaping into the arms of his looper in celebration.

Greg Norman's withdrawal from the 2010 Open Championship opened the door for Day to make his Major debut at St Andrews. He would make the cut and finish in a tie for 60th place.

At the PGA Championship in August, Day shot a final round of 66 to finish in a tie for 10th with Matt Kuchar. By the end of the 2010 season, Day was ranked 33rd in the world.

In 2011, he would finish as runner-up at both the Masters and the US Open. At Augusta, he was tied for the lead several times during the final round, but a strong finish from Charl Schwartzel denied Day his first Major championship.

After a mini-slump in 2012, Day had a few more close calls with Major glory in 2013, finishing third at the Masters and runner-up at the US Open.

Coming into the PGA Championship in 2015, Day was ranked fifth in the world and had four career tournament wins on Tour. Day had won the RBC Canadian Open three weeks before, but Jordan Spieth was the clear favorite for the year's final Major.

Day held a two-stroke lead over Spieth, who was hunting a third Major that year, heading into the final round, and Day produced an assured final-round of 67 to win his first Major.

Two weeks after this triumph, Day returned to PGA Tour action with a win at The Barclays.

After claiming his seventh PGA Tour win at the BMW Championship on September 20, Day captured the world number one ranking for the first time.

The latter part of Day's career has been dogged by injuries to his neck and back, which some have attributed to his short and quick swing.

He claimed The Players Championship title for the first time in 2016 but hasn't won on the Tour since May 2018.

In 2020, Day mounted a serious challenge at the PGA Championship, finishing tied-fourth and claiming to be pain-free having done remedial work on his swing.

Day's first link to the golfing world was through his father, but his earliest mentor wasn't around to see his son win a Major, having succumbed to cancer when the future world number one was just 12 years old.

His mother is originally from the Philippines while his father was an Irish-Australian.

Day is married to American Ellie Harvey, having tied the knot with the small-town girl in 2009. The couple have three children and now reside in Westerville, Ohio.

Day revealed that he had discussed the possibility of giving up his golf career with his wife in 2019 at the height of his injury problems.

Day has an estimated net worth of $40million thanks largely to his career winnings, which are in excess of $48million.

He was ranked 69th in Forbes list of the 100 highest-paid athletes of 2016.

Day enjoys lucrative partnerships with a range of sponsors including Adidas, SAP Concur, Lexus, NetJets, RBC, Rolex, TaylorMade and Zurich. He is represented by Bud Martin of the Wasserman agency.